Sodium has 1 valence electron, which it shares with fluorine to form a covalent bond. a. true b. false

False

Explanation:

Ionic bonds are formed by transfer of electrons between metal and non metals.

Covalent bonds are formed by sharing of electrons between non metals.

Sodium atom has oxidation number of +1.

Electronic configuration of sodium:

Sodium atom will loose one valence electron to gain noble gas configuration and form sodium cation with +1 charge.

Florine atom has oxidation number of -1.

Electronic configuration of fluorine:

Florine  atom will gain one electron to gain noble gas configuration and form fluoride ion with -1 charge.

In sodium fluoride the one electron from sodium metal gets transferred to fluorine atom and thus form ionic bond.

- lead + phosphoric acid = hydrogen + lead(ii) phosphate